Positive expulsion tank



SePt- 24 1953 L M-HIRSCHFLD ETAL 3,104,526

POSITIVE EXPULSION TANK Filed March 2, 1959 5 Sheets-Sheet 1 \1`\\1\` Illu Aa. .v v :Ri

nllll INVENTORS.

DONALD M. LEncH BYc RLEs cAccloPPo ATTORNEY Sept. 24, 1963 A.

. Filed March 2, 1959 L M. HlRscHFELD ETAL v 3,104,526

' POSITIVE ExPuLsIoN TANK 3 lSheets-Sheet 2 ATTORNEY 1. M. HlRscHFELD E'rAl. 3,104,526

sept. 24, 1963 POSITIVE EXPULSION TANK 3 Sheets-Sheet 3 Filed March 2, 1959 ATTORNEY United States Patent O 3,104,526 PGSHTIVE EXPULSiSN TANK Irving M. Hirschfeld and Charles Caccioppo, Woodland Hills, Robert E. Linse, Granada Hills, and Donald M. Leitch, Van Nuys, Calif., assignors to North American Aviation, lne. Filed Mar. 2, 1959, Ser. No. 796,560

14 Claims. (Cl. 60-39.48)

This invention relates to means vfor expelling fluids from tanks, and more particularly to iluid expulsion systems wherein pressure responsive tanks or diaphragms operable over a wide temperature ran-ge are utilized for assuring the positive expulsion of substantially all tanked iuid.

lt has long been .a problem in the operation of pressure actu-atable uid expulsion systems to ascertain that substantially 100% of the fluid stored in a tank could be removed therefrom and thus be available for use. This is particularly true in Athe field of rocketry wherein it is virtually mandatory, from an eiiiciency and weight standpoint, that all 'ranked iluids be usable. The problem has been -most outstanding in applications wherein adverse tanl; attitude and/ or yacceleration conditions prevail. Temperature and corrosivity of the lbanked iiuids and their action upon the usual d-iaphuagins used for similar applications have also provided problems. which have not heretofore been satisfactorily solved.

The present invention overcomes these problems through the positioning of one or rnc-re extensible tanks or diaphragms within a pressurizable iluid container so as to achieve complete fluid expulsion when the diaphragm is extended by pressure into intimate Contact with the container interior. The diaphragms of this invention, in their pre-actuation condition, are constructed to contain a series of lobes or corrugations. in their surfaces. ln their post-actuation conditions their lobes have been unfolded and their external contours exactly match the internal contours of the tanks within which they are contained. The corrugations me designed to facilitate a cornplete diaphragm :actuation phase without stretching. The diaphragms are thus required to undergo a solely extending phase in accomplishing Ian essentially complete expulsion of iluid from the volumetric area delined between the diaphragm and the external tank. These diaphragm characteristics make possible the fuse of corrosion resistant diaphragm materials having the ability to retain qualities of malleability under extreme temperature and pressure conditions. The device of this invention with its positive expulsion :action may operate equally as efficiently through the p-ressurization of :a single volume regardless of whether 'a single iluid or two dissimilar fluids are to be expelled. K

It is a principal object of this invention to provide a system where-in substantially the total of a tanked fluid may be positively expelled from its container.

lt is Ia further object to provide a dual iluid expulsion system wherein essentially all of each iluid may be positively expelled from its container by the pressurization o-f a single volume.

A still further object is to provide -a sys-tem wherein a pressure responsive, corrugated diaphragm is utilized to expel tanked fluids.

A further object is to provide a pressure responsive, corrugated diaphragm which ultimately assumes the internal shape .of the tank within which it is located without stretching of the diaphragm materials when the diaphragm is pressure actuated.

Another object is to provide Ia system wherein a single pressurization expels two dissimilar iluids by extensible diaphragm actuation.

Yet .another object is to provide a syst-em wherein two dissimilar tanked fluids are simultaneously expelled by 2 the interaction :of 'a single pressurizat-ion phase and a single diaphragm.

Other objects of invention will become apparent from the following description taken in connection with the accompanying drawings in which;

FIG. l is ya partial cutaway view of a rocket incorporating a fluid expulsion system of this invention;

FIG. 2 is a sectional view taken along line 2 2 of FlG. l showing uid passage and tank end construction;

FIG. 3 is a sectional view .taken along line 3 3 of FIG. 1, illustrating the corrugated diaphragm conguration and general rocket construction;

FiG. 4 is a perspective view of la collapsible insert in the rearward portion of the rocket of FIG. 1;

FIG. 5 a cutaway view of a structural vari-ation oi the system of FG. 1 for stationary applications; and

PIG. 6 is a cross section of =a pressurizable spherical tank containing two corrugated extensible diaphragme.

Referring now to the drawings in detail, the rocket of FIGS. l, 2, 3, and 4 .is generally indicated as l. Rocket as clearly shown in FIG. l, is provided with a central iiuid container or -bodyportion 2, a forward or warhead portion 3 threadedly connected to the forward end of body portion 2, and a combusti-on chamber 4, typically welded or screwed into lafter end of body portion 2. Body portion 2 is comprised of an external cylindrical tube S of rigid construction and the components generally contained therein. An extensible tank mem-ber or container 6, alternately called la diaphragm, is disposed longitudinally within cylindrical tube 5. lt is ilexible or expansible, responsive to internal pressures 'and cooperates with tube 5 in defining an outer tank A therebetween adapted to contain a liquid propellant. The volumetric area within tank member 6 denes an inner tank B for containing a' second and dissimilar liquid propellant. A series of outer lobes 7 .and inner lobes 7a (imost clearly illustrated in FlG. 3) form ia corrugated surface over the major portion of the length of tank member 6. lt has been found that diaphragms havin-g equal bend nadii in all corrugations `are most easily deformable to their ultimate shape without structural failure. However, While equal radii are preferred, a fully operable diaphragm may be achieved even though the -bend radii of outer lobes '7 and inner lobes 7a are unequal. While the diaphragm oi HG. 3 is shown as having eight corrugado-ns, the number used may be varied to meet operational requirements. The forward end of tank member 6 flares outwardly at da, its cornigations gradually diminishing until the tank niember .assumes Va cylindrical shape at 4its extreme forward end 5b. End 6b is iitted tightly and sealed between cylinrical tube 5 and the outer periphery of a forward closure plate 8. It rnay be secured in such position by bnazing, welding, .or otherwise bonding in :a Huid-tight relationship. Tank member 6 at .its rearward end 6c flares outwardly over a portion of its periphery to for-rn a series (four in this contigui-ation) of rnodiiied corrugations or crescent shaped channels l1 (see FIGS. l, 2, and 4).

Partially nested within each channel 11 is :an insert l2.

Insert l2, as clearly illustrated in FlG. 4, is generally crescent-shaped over most of its length. A rearward portion i4, nested in channel 11, includes a pluality of stiileners or ribs 15 extending outwardly into contact with the inner periphery of cylindrical tube 5. Passageways 16, -dened between rearward portion 14, ribs 15, and tube 5, are maintained throughout system operation by the resistance to deformation ofribs 15. Integral with and extending forwardly from rearward portion 14 is :a collapsible portion 17. This collapsible portion, essentially tlat at its forward extremity, lbecomes progressively more curved as it proceeds rearward to a point of maximum curvature (approximately half-round) just forward of ribs 15. It then ilares outwardly into the crescent shape of rearward portion 14. Collapsible portion 17 is perforated over its entire length to facilitate free fluid ow and sufficiently flexible to be capable of deformation to match the internal contour of tube 5.

A longitudinally extending tube or diaphragm support 18, having perforations 13, is coaxially located Within tank member 6 and supported at its forward end `by forward closure plate 8. An end piece 2t) provides rigid support for the after end of diaphragm support 18 through integral web members 21, as shown, or through similar structural connectors. When web 2l is used, cutouts 21a must be provided through the web to accommodate fluid flow therethrough.

An annular support lmember 22 has a front portion 23 secured in fluid tight relationship within tube support end piece 29 and a rearwardly extending collar 24 similarly secured Within tube 5. Fnont portion 23 contains a radial iluid passage 25 leading from tank A and an axial fluid passage 26 leading from tank B. Burst diaphragms 27 and 28 are secured across passages 25 land 26 respectively by collar inserts 29 fand 39. Combustion chamber 4 is threadedly connected to the inner periphery of colla-r 24.

An injector and gas generator assembly generally indicated as 31 is coaxially and slidably installed tank support 18 and annular support member 22 and axially retaine-d in abutment with support member 2v2 by the rearward abutment of :combustion chamber 4. A radi-ally disposed integral injector head 32, pressure sealed with respect to adjacent components, contains a series of passages and annular grooves interconnecting radial pa'ssage 2S and axial passage Z6 with combustion chamber 4 to provide for propellant injection and A gas generator grain-containing tube portion 33 extends axially forward from injector head 32 and tits in a sealed relationship within front portion 23 of support member 22 and within tank support 18. Grain tube 33 is substantially filled with a gas generator grain 34 of solid consistency, a typical composition, .for example, having'ammonium nitrate and methyl acrylate as its principal yingredients. A plug 3S having a diaphragm 36 therein is iixed at one end of a central passage 37 in grain k34 within the forward portion of grain tube 33. A pipe 38 may be fixed within an opening through plug land extend axially `forward to direct gases to impinge upon a curved surface 9 of closure plate 8.

A conventional igniter squib 40 is located within the after end of 4grain passage 37. An electrical conductor 41 is attached to squib 40 from an electrical power source (not shown) to ignite the squib.

Prior to system actuation outer tank A and inner tank B are filled propellants yand the rocket placed in a launcher (not shown). rl`he propellants may be corrosive in nature since all structural parts in the system vare capable of being compatible with such propellants. Upon tiring squib the ame therefrom is directed forwardly into passage 37. Gas generator grain 34 is ignited and burns in the peripheral area of passage 37, progressing radially outward until all lof the grain is consumed. As the gra-in burns, large volumes of hot gaseous products are produced, the pressure within passage 3-7 rises and diaphragm 36 is vbuirst, allowing the gaseous products to escape into pipe 38 and proceed therethrough. They then impinge upon surface 9 of closure plate 8 and are redirected into tank B, causing the pressurization of that tank. The burning of the squib .and the gas generator grain also burn out a consumable plastic closure disc 42 at the rear of the squib and a portion of the hot gases are directed rearwardly through an igniter passage 43 into combustion chamber 4, providing propellant ignition.

As the liquid propellant contained Within tank B becomes pressurized, forces are exerted by the propellant and the gaseous products both radially outwamd and rearwardly. Pressrized propellant within axial passage 26 bears against and bursts diaphragm 2d. The bursting of the diaphragm allows pressurized propellant to -move` through passage 26 and into interconnected injector passages from where it is ultimately injected into the `combustion chamber. Simultaneous with :the bursting of daphragm 28, the gases and the pressurized propellant in tank B, acting radially outward against diaphragm 6 initiate the outward unfolding of diaphragml lobes 7. The diaphragm thus bears against and pressurizes the liquid propellant in external tank A. Both the internal and the external tanks `are thereby pressurize simultaneously -by a single pressurizing device actuatable Within the inner tank.

As the propellant within outer tank A lbecomes pressurized, the propellant within radial passage 25 beans against and bursts diaphragm 27. This bursting is approximately simultaneous with the bursting of diaphragm i 28. The propellant from tank A enters injector passages and is injected into combustion chamber 4 Where it is mixed with the propellant from tank B. The mixed pro pellants (oxidizer and fuel) are ignited by the igniter flame issuing from passage 43, resulting in a thrust vector and rocket movement in the direction indicated by arrow 44. Y

As the propellant tanks begin to empty, the rocket accelerates forwardly and the propelllants are forced to the y rear of the tanks by acceleration forces. Pressurizing gases 'are thereby trapped forwardly of the propellant and prevented from traversing the injector passages. As the outer propellant tank A empties and lobes 7 are progresf v sively unfolded from front to rear, expandable tank 6 gradually assumes a shape identical to the inner surface of tube S. Insert l2, through which propellant is flowing at this time, when contacted by expandable tank 6 is of Y sufficient stilness to resist deformation until that portion of expandable tank 6 forwardly of insert 12 has assumed it ultimate shape, i.e. contacting tube 5. Beginning at its forward end, collapsible portion 17 of insert 12 is then progressively deformed until its entire length forwardly of ribs 15 is forced into Contact with tube 5. This ability of portion 17 to be deformed progressively makes possible the gradual diminution of the iiuid channel formed between portion 17 and tube S until it ultimately disappears and the propellant contained in that channel is expelled. n

It is desirable, as set forth above, that the corrugations of expandable tank member 6 be designed in such fashion as to enable them to gradually unfold as propellant expulsion progresses. In order that this might be achieved,

tank member 6 must have an external peripheral length` at any particular position along its length which essentially matches the internal peripheral length of tube 5 adjacent Y that position. tank member 6 The relative When so constructed and fully expanded will have no fol-ds remaining in its surface. capacities of the tanks A `and B: may be varied as desired by retaining the same peripheral length support 18 for best structural rigidity prior to system operation.

Essentially the Same structure as described aboveis if y usable as a stationary fluid expulsion and mixing system; However, ythe rocket propellant expulsion system of FIG. 1, when applied to a stationary configuration, is stood on its after end allowing gravity, rather than acceleration forces, to maintain tural variation is illustrated in FICr.V 5.

Here the lluid expulsion and mixing system 50 may be inner extensible diaphragm 52,

ly the characteristics of insert: 12 as illustrated in FIGS.

1 4, and an injector or mixerr(not shown) similar to theV injector portion of the injector and gas generator assembly 31 of FIG. 1.

proper liquid positioning. This struc-V Although this insert and injector are not specifically illustrated in `FIG. 5 it is to be understood j that their incorporation in a-manner similar to that of like elements in FIGS. 1 4 is assumed. The gas generator 34 of FIG. l and its supporting structure may be replaced in this conguration with pressure cylinder 53 containing a pressurant compatible with the fluid stored within extensible tank member 51. `Cylinder 53 may be conveniently affixed to .a plate 54 (replaces closure plate 8 of FIG. l) internally of the tanks or externally thereof as design requirements'dictate. A cap member 55 (in place of warhead 3), affixed to and Sealed with respect to the outer cylindrical tube, may contain a conventional valve means 56 for the release of the pressurant. The pressurant, when released from cylinder 53 by opening valve means 56, is directed into the interior of the extensible -tank member through a series of perforations 57 contained in plate 54. The resultant liquid flow `and diaphragm extension is identical to the action in the FIG. l configuration. However, here the mixed liquids, rather than being burned as propellants, may be collected in basin 5S (replaces combustion chamber d) and transmitted through line 59 to a desirable remote location to serve their useful function.

FIG. 6 represent .a further structural variation of 4the expulsion system and the extensible diaphragm of this invention. Therein two separate diaphragms are so situated within a spherical container as to make possible the expulsion of like or unlike fluids from separate compartments while pressurizing in a single separate compartment. Two identical hernispherical shells 60 preferably have internal anges 61 radially extending from their points of maximum diameter and positioned so that flange surfaces 62 face one another. Internal surfaces 63Vof shells 60 may optionaly include inwardly facing fiat annular surfaces 64 tangential to surfaces 63 and adjacent to flanges 61, their function to be defined below.

An annular manifold ring 65 has an upstanding member 66 clamped in a fluid-tight relationship between surfaces 6?. .and an annular crossbar integrally fixed to the internal periphery of member 66. `Crossbar 67 is physically enclosed within the sphere formed by shells 6i) and spaced from surfaces 64.

A pair of similarly constructed diaphragme y63 have 'a series of annular corrugations 69 upon their surfaces. Flanges 7G are directed toward one ano-ther and extend axially from the periphery of diaphragms 68. A radially extending ange 731 (shown illustratively upon right hand ange 79) may optionally be attached to the free end of the axial flanges 7G. Fianges 7 (i are clamped over opposite sides of crossbar 67 in a spaced relationship from shell surfaces 6d. Diaphragms 68 are constructed so that when corrugations 69 are unfolded the diaphragms are hemispherically-shaped and exactly match the contours of surfaces 63. Prior to diaphragm extension, diaphragm central portions 72 are essentially flat and located adjacent one another near the center of the sphere formed by hemisphere 6ft. The extending or unfolding phase through which diaphragm 63 pass in assuming their ultimate hemispherical shapes is accomplished with substantially no stretching of the diaphragme. This is achieved by designing and manufacturing the diaphragms such that the length of a peripheral radius line drawn on the diaphragm surface is the same length as a peripheral radius line drawn on surface 63. Additionally, the distance from the center of the diaphragm to any point on the diaphragm remains the same both before and after diaphragm extension. By meeting rthese conditions with respect to every peripheral line of the diaphragm, no diaphragm material stretching is necessary upon extension in assuming the ultimate shape.

A pair of Support rings 73 serve the dual function of clamping anges 70 about annular crossbar 67 and acting as diaphragm supports during the operational phase. The ring may be shrunk in place, providing a constant inward radial force or it may be bolted. A hermetic seal between `the diaphragm flanges and crossbar 67 may be obtained by applying -to that region a conventional sealing and bonding gasket material (illustrated as 73b) prior to clamping. A radial ange such as 74a (shown adjacent ange 7M) may optionally be provided upon the clamping end of the support rings to provide added support for the diaphragm flanges. Perforations 75 `are provided through support ring 73 to facilitate fluid flow into annular passages 76, formed between support lings 73 and surfaces 64. Where needed, the outer extremities of support rings 73 may be spaced from shells 6d, providing other fluid paths. Tanks or fluid compartments 77 are formed between diaphragms l655 and shells 6ft. An ullage and pressurizing chamber 78 is defined between the diaphragms.

All external fluid ktransfer and pressurizing ports are preferably contained in manifold ring 65. A pressurizing passage 79 extends radially through ring 65. Ring 65 similarly contains fluid ports 80 and 81 communicating between the rings external surface and separate fluid channels 76. Utilizing these separate fluid ports, the expulsion tank is adapted to simultaneously expel uids from both tanks 77. If like fluids are contained in both tanks they may be expelled through a common line by simply eliminating either port Sil yor S1 and inter-connecting (not illustrated) the remaining port with both annular channels 76. Ports Si) and Si may also serve as tank filler ports. Alternately, other similar ports may be provided through manifoldring 65, or through the upper portions of the shell walls. Ports for air escape during the tank filling operations may be similarly provided.

Two identical diaphragm supports 82, essentially matching the shape of diaphragms 63, are placed between the diaphragms with their outer free edges'bearing against the crossbar 67 to prevent diaphragm deformation during tank filling or under acceleration or sloshing conditions prior to system pressurization. These supports must contain perforations or cutouts S3 (as representatively shown in FIG. 6) to provide an area through which pressurizing gases may pass. They are preferably made from a light, rigid material, e.g. plastic, aluminum, etc., and compatible with the pressurizing gas'and with the fluids, even though not normally in Contact therewith, to offer maximum safety in case of a diaphragm leak. vOperationally the tanks are first filled with fluid. A pressurizing gas is then introduced from a conventional pressure source (not shown) in a desired sequence with conventional shutoff valves installed in exit lines (neither shown), through port 79 and into ullage chamber 78. The pressurized gases pass from ullage chamber 78 through the perforations or cutouts 83 in diaphragm supports 82 and begin to actuate the diaphragme. As diaphragm extension progresses, the corrugations, beginning from the center and proceeding outwardly, tend to unfold in sequence and become continuous with the central portion of the diaphragm. This sequencing is facilitated by the varying amplitude of the corrugations. When extension is completed, each diaphragm half is essentially hemispherical in shape, matching and intimately contacting the internal surface of its adjacent` shell. Upon diaphragm actuation, the fluids contained in tanks 77 pass through perforations 75 and between the free end of support ring 73 and hemisphere surface 62. Fliuds entering annular channels 76 are transferred out of the system through uid ports fl and Si. When diaphragm 63 has extended to its final position and assumed its ultimate hemispherical shape, having performed its extending `operation with no stretching of diaphragm materials, essentially the total fluid contained within the tank has been ejected.

The expulsion system of FIG. 6 is fully operable regardless of the attitude of the tank or the acceleration conditions under which it operates.

In choosing a material from which the diaphragms of this invention are to be made, the conditions under which they are to operate must be fully considered. The material must have the qualities of flexibility and malleability throughout the temperature range within which the system will operate. The preferred material for low temperature applications, for corrosive iiuid compatibility, and from an ease of manufacturing standpoint is 6061-80 aluminum. lt has been found through experimentation that a diaphragm made from this metal, with a thickness of from .025 to .032 inch, may be fully extended and `expel a fluid from its tank by applying an internal pressure of i8 p.s.i. maximum in a tank of approximately 2t) inches inside diameter. Smaller tanks require thinner diaphragms and larger tanks may use thicker diaphragms. Materials other than aluminum, for example, copper, soft iron, nickel, lead, etc., may also be used in fabricating the diaphragms, dependent upon the particular system iiuids used and upon the system temperatures.

When this invention is utilized as a loi-propellant rocket system such oxidizers as liquid oxygen, liquid uorine, liquid nitrogen, various acids, e.g. red turning nitric acid, White fuming nitric acid, etc., may be used with such fuels as turpentine, alcohol, unsymrnetrical dimethylhydrazine, ammonia, etc. However, the fluids used are dependent only upon being compatible With system mate-V rials.

Although the invention has been described and illustrated in detail, it is to be clearly understood that the same is by way of illustration and example only and-is not to be taken by Way of limitation, kthe spirit and scope of this invention being limited only by the terms of the appended claims.

We claim:

l. A iiuid expulsion system comprising a container, means in said container deiining an opening therethrough, corrugated metal diaphragm means dividing said container into chambers, and means forming fluid exits from each of said chambers, said diaphragm means having a peripheral surface area substantially equal to an interior surface area of said container, said opening commumeating with said diaphragm for the admission of pressurization to extend said diaphragm means into contact with said internal surface of said container.

2. A iiuid expulsion system comprising a pressure vessel, extensible, corrugated metal diaphragm means positioned within said vessel and forming fluid-tight chambers therein, said `diaphragm means being resistant to and malleable under extremes of temperature and pressure and having an extended surface contour matching an internal surface contour of said pressure vessel, means in said vessel forming fluid exits from said chambers, and means for admitting gaseous pressurants to said system so as to cause said diaphragm means to be extended toward said vessel.

3. A tanking and expulsion system for two dissimilar liquids comprising a cylindrical outer container, a peripherally-corrugated, iiexible metallic container extensible upon internal pressurization to intimately contact an inner wall surface of said outer container and fixedly retained within said outer container, closure means joining adjacent ends of said containers, means defining a fluid exit from each of said containers, mixing means connected to said exit means, and pressurizing means aiiixed so as to permit the internal pressurization of said flexible container.

4. A system for the positive and simultaneous expulsion of two dissimilar tanked iiuids comprising a sealed outer container, a peripherally-corrugated extensible container internally secured to and having its interior sealed from communication with said outer container, said extensible container before actuation thereof having a peripheral surface area substantially equal to the internal surface area of said outer container, means defining a fluid exit from each of said containers, a pressure sensitive closure in each of said exits, and pressurizing means of communicating with the interior of said extensible tank for extending same into intimate contact with said outer sov container, bursting said pressure sensitive closures, and simultaneously expelling said ldissimilar iiuids,

5. A system for the positive and simultaneous expul internal diameter of said cylindrical container, said container and said diaphragm having their ends connected and closed, the volumetric area Within said diaphragm defining a first iiuid tank and the volumetric area between said container and said diaphragm defining a second fluid tank, an after end portion upon said diaphragm having formed therein a series of alternately located longitudinal lands and valleys substantially parallel to and iiaring from said corrugation, said lands internally contacting said cylindrical container and said valleys cooperating with said cylindrical container to form fluid channels; means defining a fluid entry and a iiuid exit from each of said tanks; a perforated support member fixed coaxially Within said expansible diaphragm and internally supporting the corrugations of said expansible diaphragm; and pressurizing means operably connected to said perforatedsupport member for communication with this interior of said first tank whereby pressure may be applied to said first tank to simultaneously expel iiuid contained therein, expand said expansible diaphragm and expel fluid'from said second tank.

6. The invention according to )claim 5 wherein said corrugations upon said expansible tank are composed of internally extending lobes of approximately equal bend radii.

7. The invention according to claim 5 'wherein ribbed inserts are secured within said iiuid channels, a collapsible portion integral with each said insert extending forwardly therefrom, said collapsible portion being perforated over its iength and curved progressively deeper from front to rear, said portion adapted tot be deformed to the internal contour of said cylindrical container progressively fromY its forward end lto its point of attachment to said ribbed insert upon actuation of said pressurizing means.

8. A bi-propellant rocket expulsion system compris-` ing a rigid cylindrical tank; a peripherally-corrugated expansible tank member coaxially positioned WithinV said cylindrical tank, said expansi'ble tank member 4having an expanded diameter substantially equal to the internal diameter of said cylindrical tank, said cofrrugattions being composed of internally and externally extending lobes of approximately equal bend radii; a propellant injector; each of `said tanks having a closed forward end and an after end xed to said injector; said injector containing passages communicating between each of said tanks and a combustion chamber; pressure responsive burst diaphragms closing said passages; a tubular member internally fixed between the ends of said corrugated tank member and supporting said internally extending lobes; said expansible tank having formed in the after end thereof a plurality of longitudinal lands andva-lleys substantially parallel to and iiaring from said 'corrugations, said lands contacting said cylindrical tank and said valleys cooperating with said cylindrical tank to form fluid channels; support members afiixed Within said channels to prevent collapse of said channels; and pressurizing means in said tubular member and comrnuriicating therethrough with the interi-or of said expansible tankV member whereby pressure may be applied internally of saidk expansible tank member, 'bursting said diaphragms, n and simultaneously causing the expansion of said expatnsible tank and injection of uids from said tanks into the combustion chamber.

9. A positive iiuid expulsion system comprising a tank, two extensible, corrugated metal diaphragms secured therein, each ott said diaphragms forming a fluid chamber with a portion of said tank and having an extended contour substantially matching said portion of said tank, a combination ullage and pressurizing chamber being formed between said `diaphragms, fluid port means in communication with each -of said chambers and port mea-ns for introducing pressurizing gases between said diaphragms to cause extension of said diaphragms.

l0. The invention of claim 9 whe-rein a manifold ring is provided between two hernispherical portions of said tank and -Wherein said fluid ports and said port means are contained within a common manifold ring.

11. In combination two anged, hemispherical tank halves, an annular manifold rin-g clamped between said flanges and extending internally thereof, an extensible, corrugated metal diaphragm iixed to each side of said ring and internally spaced from said ltank halves, each of said diaphragms deiining a fluid chamber with one of said ltank halves and having a peripheral surface area substantially equal to an internal surface area of said fluid chamber, an tillage and pressurizing chamber deiined between said diaphragms, pressure accepting port means through said manifold ring communicating with said ullage chamber, and means in said manifold ring defining iluiid exits from said iiuid chambers.

12. The invention according to claim 1\1 wherein the depth of said corrugations progressively increases from the innermost to fthe outermost thereof.

13. A fluid expulsion system comprising two hemispherical tank halves, each tank half having an annular tlange radially extending from its opening; an annular manifold ring clamped between said flanges and extending internally thereof, said ring having an annular crossbar member fixed to its internal periphery; two ioppositely directed, corrugated, `extensible diaphragms, each of said diaphragms having an annular ange attached to its periphery and clamped about a portion of said crossbar member; an annular support ring clamped about each of said diaphragm flanges and securing said diaphragm upon said crossbar in a duid-tight relationship with said cross- 10 bar; each of said diaphragns yforming a fluid compartment with one of said tank halves and having a surface area substantially equal :to an internal surface area of said fluid compmtment; said diaphragms definingV therebetween an ullage and pressurizing chamber; means in said manifold ring defining iluid ports communicating Ibetween said compartments and externally connected ilu-id lines; means in said manifold ring defining a pressurizing port communicating `between said ullage and pressurizing chamber and the external periphery off said ring; whereby pressurizing gases may be introduced between said diaphragms for extending said diaphragme into intimate contact with said tank halves and expelling iluids from said compartments.

14. A system for the positive and simultaneous expulsion of two similar uids comprising a container, at least one corrugated extensible diaphragm secured within and separating said container into noncornmunicating chambers, said diaphragm adapted for extension into intimate contact with internal surfaces of said container in response toA pressure internally thereof, fthe diaphragm having a peripheral sur-face area substantially equal to the container inner surface area contactable thereby, a perforated diaphragm support means xed Within said container in initial contact with said diaphragm corrugations.

References Cited in the le of this patent UNITED STATES PATENTS 2,507,778 Frey May 16, 1950 2,711,630 Lehman June 28, 1955 2,762,534 Kish Sept. 11, 1956 2,836,963 Fox June 3, 1958 2,844,938 Longwell July 29, s 2,859,808 Youngqnist et al Nov. 11, 1958 2,939,281 Conyers June 7, 1960 2,953,304 Sellinger Sept. 20, 1960 2,955,649 Hoffman Oct. 11, 1960` 

8. A BI-PROPELLANT ROCKET EXPULSION SYSTEM COMPRISING A RIGID CYLINDRICAL TANK; A PERIPHERALLY-CORRUGATED EXPANSIBLE TANK MEMBER COAXIALLY POSITIONED WITHIN SAID CYLINDRICAL TANK, SAID EXPANSIBLE TANK MEMBER HAVING AN EXPANDED DIAMETER SUBSTANTIALLY EQUAL TO THE INTERNAL DIAMETER OF SAID CYLINDRICAL TANK, SAID CORRUGATIONS BEING COMPOSED OF INTERNALLY AND EXTERNALLY EXTENDING LOBES OF APPROXIMATELY EQUAL BEND RADII; A PROPELLANT INJECTOR; EACH OF SAID TANKS HAVING A CLOSED FORWARD END AND AN AFTER END FIXED TO SAID INJECTOR; SAID INJECTOR CONTAINING PASSAGES COMMUNCATING BETWEEN EACH OF SAID TANKS AND A COMBUSTION CHAMBER; PRESSURE RESPONSIVE BURST DIAPHRAGMS CLOSING SAID PASSAGES; A TUBULAR MEMBER INTERNALLY FIXED BETWEEN THE ENDS OF SAID CORRUGATED TANK MEMBER AND SUPPORTING SAID INTERNALLY EXTENDING LOBES; SAID EXPANSIBLE TANK HAVING FORMED IN THE AFTER END THEREOF A PLURALITY OF LONGITUDINAL LANDS AND VALLEYS 